Server sends emails ever 30 minutes
 

I recently configured postfix and stopped sendmail.

I am now getting Delivery Status Notification (Failure)messages to my home email every 30 minutes. First thought was a cron job. Checked it and sure enough. Commented the line out, but still getting them ever 30 minutes.

Is there another crontab? Do I need to flush this one after making a change or restart some service?

Thank you

If it is due to an addressing error, you get this every time the mail server attempts to deliver a message. And if it can't be delivered, it will try again as the message will be attempted again as it sits in a mail queue (usually /var/spool/mqueue) until removed, or until the configured expiration time reached.

Hi Jpollard,

I understand the address error part, but not why an email was being sent every 30 minutes. I rebooted the machine, and it has stopped. Which makes me think just updating using "crontab -e" might not be enough, and I need to restart the service after making the changes.

crontab -e is sufficient. The only time that isn't is when you edit the crontab maintained by the system directly.

This is because crond keeps a list in memory of all users entries, sorted by start time. Editing directly doesn't get crond to reload the file, which crontab -e does.

I usually keep a crontab in my home directory and edit that, then use crontab to load it. That way I have a backup and can reload if a system update (or alternate root) gets used that wipes it out (or doesn't have the current one).